The development of technology is essential for the advancement of society, however, the dramatic changes we have been experiencing since a little over 10 years ago have completely changed our environment, requiring our vision to adapt to this new landscape.
With the arrival of personal computers and their implementation in the workplace, the first symptoms associated with prolonged use of screens began to appear. However, the disruption of the market by smartphones and the exponential growth of the number of hours different digital devices are used has caused the prevalence of these systems and the suspicion that certain refractive errors and conditions may be associated with these hours of use to skyrocket.
Many studies indicate that the number of hours one spends in front of a screen continues to exponentially increase with the use of new devices throughout society. Not surprisingly, according to the latest data published by the consulting firm Nielsen, we now spend the majority of our time with our eyes set on a screen (TV, video game console, smartphone, etc.). According to this report, the hours of use for televisions, video game consoles, and applications and the Internet on our smartphones and tablets (Figure 1) increases every quarter, with the adult population of the United States spending more than four hours a day watching television and over two hours a day using applications or the Internet on their smartphones1.
The American Academy of Optometry describes computer vision syndrome (CVS) as a group of vision-related problems that result from prolonged computer, tablet, e-reader, and cell phone use2. Despite this description, there is no consensus in the scientific or medical community on the definition of computer vision syndrome, nor is there consensus regarding its diagnosis, making it difficult to estimate how many people may suffer from it.
In many non-scientific publications one can find data estimating the prevalence of CVS to be around 90% in people who frequently use data viewing screens (e.g., smartphones, computers, tablets, etc.). However, if the scientific literature is consulted, one will find that there are peer-reviewed questionnaires that allow physicians to understand and compare the prevalence of this syndrome among the population of Spain. These studies must be expanded as there are few of them and the findings are not very extensive3.
To cite a few examples of studies carried out in Spain in populations of different ages and occupations, in 2016, Tauste et al. found that in a sample of workers who frequently use data viewing screens, 50% suffer from CVS, a datum that increases to 60% in contact lens wearers4. Moreover, a study conducted at Universidad Europea that is pending publication found a prevalence of 32% in the university population.
Apart from CVS, whose symptoms include headache, dry eye, and blurred vision, there are other vision-related and general concerns about this increase in hours spent using new technology.
These concerns include the effect that blue light emitted by digital devices may have on health5. Within the spectrum of visible light, blue light is the most energetic and it reaches our retinas due to its characteristics. Although there is a great deal of controversy on the matter, several studies relate this blue light to CVS and to potential development of pathologies of the retina like age-related macular degeneration6. Additionally, exposure to blue light causes decreased melatonin synthesis, which is directly related to insomnia7.
Finally, it also appears that there is a relationship between the increase in the prevalence of myopia around the world and the increase in hours children spend using digital devices. According to the last study carried out by the Universidad Europea Vision Research Group on over 3,500 children between the ages of 5 and 7, 30% spend more than two hours per day with cell phones, tablets, etc., and this percentage increases to 33% among near-sighted children8.
Technology’s effects on vision are sometimes reversible, as is the case with symptoms related to computer vision syndrome, but in other cases they are not, as occurs with retinal damage or the appearance of myopia. Ideally one should follow the recommendations of vision experts to prevent conditions arising from the use of technology from appearing, as prevention is the best strategy to address these conditions9.
Rest breaks are essential to reducing the risk of suffering from computer vision syndrome and to curb symptoms from getting worse. That is why users of any kind of screen are recommended to take frequent breaks following the 20/20/20 rule: Look away from your screen for 20 seconds every 20 minutes, focusing on a point 20 feet (6 meters) away.
Apart from rest breaks, there are other ergonomics recommendations that apply to using a computer10 such as:
- Lighting: Prevent reflections on screens as much as possible and adjust their settings
- Position: You should keep the computer screen under your eyes so that the highest part of the monitor is at the height of your eyes
- Blinking: Although it is a reflex, we actually blink less in front of screens so you should regularly remind yourself to blink voluntarily
It is very important to remember that all other devices should be kept at the appropriate distance, avoiding bringing them too close to your eyes and that the brightness levels should be adjusted to your surroundings. In addition, avoiding using your cell phone right before bed or turning on the screen at night is recommended to prevent sleep disturbances7.
There are now filters to reduce the amount of blue light reaching your retina that can be found in glasses, contact lenses, and built into some screen protectors.
In the case of children, it is important to remember that they are less conscious of the amount of time they spend on devices and their great adaptability to certain situations can cause them, when unchecked, to excessively use these devices for prolonged periods of time, with the health consequences entailed by said use11. You should also remember that children have no trouble adapting to their surroundings, so adults need to help them adjust the lighting and the device’s settings (brightness, font size, etc.) so that they are appropriate.
In addition to what we already know, we should watch out for future technology developments, which cause us to have to pay attention to the visual requirements that these new advancements entail.
Today professionals are working to better understand how the recent arrival of virtual reality and its expansion into different fields affects or may affect our vision12.
- com. (2018). The Nielsen Total Audience Report: Q1 2018. [online] Available at: https://www.nielsen.com/us/en/insights/reports/2018/q1-2018-total-audience-report.html# [Accessed Dec 10, 2018].
- org. (2018). Computer Vision Syndrome. [online] Available at: https://www.aoa.org/patients-and-public/caring-for-your-vision/protecting-your-vision/computer-vision-syndrome [Accessed Dec 10, 2018].
- Sheppard AL, Wolffsohn JS. Digital eye strain: prevalence, measurement and amelioration. BMJ Open Ophthalmology. 2018;3: e000146. doi: 10.1136/bmjophth-2018-000146
- Tauste A, Ronda E, Molina M-J, Seguí M. Effect of contact lens use on Computer Vision Syndrome. Ophthalmic & Physiological Optics: The Journal of the British College of Ophthalmic Opticians (Optometrists). 2016;36(2):112-119. doi:10.1111/opo.12275.
- Moon J, Yun J, Yoon YD, et al. Blue light effect on retinal pigment epithelial cells by display devices. Integrative Biology: Quantitative Biosciences From Nano to Macro. 2017; 9(5):436-443. doi: 10.1039/c7ib00032d
- Algvere PV, Marshal J, Seregard S. Age‐related maculopathy and the impact of blue light hazard. Acta Ophthalmologica Scandinavica. 2006;84(1), 4-15. doi: 10.1111/j.1600-0420.2005.00627.x
- Shechter A, Kim EW, St-Onge MP, Westwood AJ. Blocking Nocturnal Blue Light for Insomnia: A Randomized Controlled Trial. Journal of Psychiatric Research. 2018; 96, 196-202. doi: 10.1016/j.jpsychires.2017.10.015
- Alvarez-Peregrina C, Sanchez-Tena MA, Villa-Collar C. Prevalencia de errores refractivos en niños de 5 a 7 años. [Prevalence of Refractive Errors in Children 5 to 7]. Gaceta de Optometría y Óptica Oftálmica. 2018; 539, 1-5
- Coles‐Brennan C, Sulley A, Young G. Management of Digital Eye Strain. Clinical and Experimental Optometry. 2018; 1-12. doi: 10.1111/cxo.12798
- Tribley J, McClain S, Karbasi A, Kaldenberg J. Tips for Computer Vision Syndrome Relief and Prevention. Work. 2011: 39(1), 85-87. doi: 10.3233/WOR-2011-1183
- Lissak G. Adverse Physiological and Psychological Effects of Screen Time on Children and Adolescents: Literature Review and Case Study. Environmental Research. 2018; 164, 149-157. doi: 10.1016/j.envres.2018.01.015
- Clark AJ, Yang P, Khaderi KR, Moshfeghi AA. Ocular Tolerance of Contemporary Electronic Display Devices. Ophthalmic Surgery, Lasers & Imaging Retina. 2018; 49 (5), 346-354. doi: 10.3928/23258160-20180501-08